Traditional mainframe computer configurations provided for user interface to the computer through computer terminals which were directly connected by wires to ports of the mainframe computer. An example of such a terminal is an IBM 3270 or IBM 5250 type terminal which may communicate with a mainframe (or host) using a Telnet protocol. A Telnet protocol for a terminal such as an IBM 3270 or an IBM 5250 typically provides for structured grouping of data stream transmissions with a series of control characters followed by a block of displayable characters with a data stream comprising a plurality of sequentially transmitted control character blocks followed by displayable character blocks.
As computing technology has evolved, processing power has typically moved from a more central computer model to a distributed environment with local area networks connecting individual work stations to wide area or internet networks linking a number of different local networks through devices such as, for example, routers. Furthermore, due to infrastructure limitations and cost, components of the "network" linking two devices wishing to communicate may include a low through-put component such as a wireless network link. Central mainframe computers continue to play a role in the networked environment. Accordingly, using structured protocols such as the Telnet protocol are still in use. These applications may communicate with users over the network to terminals such as an IBM 3270 or, alternatively, to microprocessor based work stations executing software applications which allow the computers to act as a terminal.
Communications from a terminal (or terminal emulator) to a host are typically disadvantaged particularly on lower through-put network legs, such as wireless legs (or highly congested legs which are effectively bandwidth limited), where bandwidth limitations result in slower response time for communications between the terminal emulators and the host application. In the extreme, protocol timeouts may even cause transmission errors and resulting retransmissions or even inability of the communication system to operate. Thus, utilizing wireless technology, or any low-speed communication technology, with terminal emulator or other structured type data protocols exacerbates the weaknesses of the wireless technology.
A further problem with terminal to host communications relates to session start up. Sessions may be intentionally discontinued and restarted later. Problems may also be encountered where random session failures occur; causing unplanned loss of connection to the host. Additional problems may be encountered with identification of sessions for start up where multiple sessions are active concurrently for a single client/server (terminal/host) pair.